JPS6145252Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention provides a working arm that can be vertically swung by a fluid pressure cylinder provided on the lower side of the working arm, and a soil removal plate can be driven and raised and lowered under the working arm. Regarding the installed work vehicle.

For example, the above-mentioned work vehicle has an excavation bucket attached to the tip of the work arm and uses the earth removal plate as an outrigger when performing trench digging work by repeatedly digging and moving the vehicle body. There is a tendency for the work arm to be lowered while the board remains raised, resulting in an accidental collision between the upper edge of the earth removal board and the cylinder for operating the work arm, resulting in damage to the cylinder. There was an inconvenience.

The present invention has been made in view of the above-mentioned circumstances, and aims to solve the above-mentioned disadvantages by adding rational means.

Hereinafter, embodiments of the present invention will be described based on illustrative drawings.

As shown in Fig. 1, a swivel base 2 is installed on the top of a traveling machine base equipped with a crawler traveling device ₁ so that it can be driven and rotated around the vertical axis The support arm 3a of the plate 3 is connected to the hydraulic cylinder 4.
The engine 5 and the driver's seat 6 are mounted on the swivel base 2, and an arm support bracket 7 is vertically mounted on the horizontal center of the front side of the swivel base 2 using a hydraulic cylinder 8. The first working arm 9 is attached to the bracket 7 so as to be driveable and rotatable about the axis _X2 , and the first working arm 9 is attached to the bracket 7 so as to be movable up and down about the horizontal axis by means of a hydraulic cylinder 10 provided on the lower side thereof.
A second working arm 11 is attached to the first arm 9 so as to be movable around the horizontal axis by a hydraulic cylinder 12, and a bucket 13 is attached to the second arm 11 by a hydraulic cylinder 14 so as to be movable around the horizontal axis. The dozer/backhoe work vehicle is configured such that it can be driven and moved on the dozer and backhoe and can perform dozer work and backhoe work.

As shown in FIGS. 2 and 3, the earth removal plate 3
A cover body 15 that covers the lower part of the hydraulic cylinder 10 for the first arm 9 located above is pivoted to the hydraulic cylinder 10 so as to be swingable up and down about the horizontal axis Y of the rear end. And spring 1
6, the bolt 17 is attached in a state in which it is urged downwardly, and the bolt 17 is used to abut and restrict the downward limit of the cover body 15.
While attached to the cylinder 10, there are two positions between the hydraulic cylinder 10 and its operating state switching control valve 18, which can be switched between a state in which oil enters and exits from the bottom side cylinder chamber of the cylinder 10 and a state in which the inhibition is released. The switching valve 19 is mounted on the cylinder 10 so that the switching valve 19 is biased to return to the blocking release side, and is pressed and switched to the blocking state by upward displacement of the cover body 15. When the cylinder 10 is shortened and the first arm 9 is lowered, when the cover body 15 comes into contact with the earth removal plate 3 or the crawler traveling device 1 and is displaced upward, the cylinder 10 shortens, i.e. , the lowering operation of the first arm 9 is automatically stopped.

In short, when performing trench excavation work by repeatedly digging and moving the vehicle body while using the earth removal plate 3 as an outrigger, the first arm 9 may be lowered while the earth removal plate 3 is raised. Even if the hydraulic cylinder 10 is damaged due to a collision with the earth removal plate 3, it is possible to avoid damage to the hydraulic cylinder 10 due to a collision with the earth removal plate 3. In addition, by rotating the swivel base 2 and the arm support bracket 7, the lateral side of the aircraft can be rotated. Even if the first arm 9 is unnecessarily lowered too much when excavating a location, damage to the hydraulic cylinder 10 due to collision with the crawler traveling device 1 can be avoided. It's like this.

In the embodiment, by rationally arranging the two-position switching valve 19, a device for detecting the upward displacement of the cover body 15 and a device that automatically operates upon detection of the device to stop the lowering of the arm 9 are provided. Although an example is shown in which the detection device and the safety mechanism are combined, the detection device and the safety mechanism may be configured separately. That is, a limit switch or the like may be used as the detection device, and an electromagnetic switching valve or the like may be used as the safety mechanism.

Furthermore, in implementing the present invention, in addition to automatically stopping the lowering of the arm 9, the safety mechanism may be configured to use a warning device such as a buzzer or lamp to alert the worker. .

Furthermore, the present invention can be applied to work vehicles that are not equipped with the swivel base 2 or that do not rotate the arm 9 around the vertical axis _X2 . It is sufficient if damage caused by collision with the plate 3 can be avoided.

In addition, in carrying out the present invention, in order to avoid damage to the cylinder 10 due to contact with the earth removal plate 3 when the earth removal plate 3 is raised while the arm 9 remains lowered, the present invention is implemented. Along with the detection of the detection device,
It is even better to incorporate a mechanism that automatically stops the lifting operation of the earth removal plate 3.

Furthermore, when configuring the cover body 15, the supporting means thereof can be modified in various ways, such as supporting it in a manner that allows it to move up and down in parallel.

Further, the present invention can be applied not only to a working vehicle in which the bucket 13 is provided at the tip of the working arm 9, but also to various working vehicles equipped with various working devices such as an earth auger.

In summary, the present invention, in the above-mentioned work vehicle,
A cover body 15 that covers the lower part of the cylinder 10,
A device for detecting upward displacement of the cover body 10 is installed on the cylinder 10 so as to be movable up and down and biased downward, and the detection device is connected to the safety mechanism in accordance with the detection. The device is characterized in that it is connected to automatically operate the mechanism.

That is, by providing the cover body 15 that covers the lower part of the cylinder 10, direct collision between the cylinder 10 and the earth removal plate 3 is avoided,
Moreover, the safety mechanism is automatically activated based on the upward displacement of the cover body 15 caused by the collision with the earth removal plate 3, and the cylinder 10 and the earth removal plate 3 are prevented from approaching each other any further. Since this is automatically avoided, it is possible to reliably avoid the above-mentioned inconvenience in which the cylinder 10 collides with the earth removal plate 3 and the cylinder 10 is damaged, and as a result, it can be used even better. We were able to obtain a work vehicle that was in good condition.

[Brief explanation of the drawing]

The drawings illustrate an embodiment of the working vehicle according to the present invention, and FIG. 1 is a side view of the dozer/backhoe working vehicle, FIG. 2 is a partially cutaway side view of the cover body attachment part, and FIG. 3 is the same. FIG. 4 is a partially cutaway front view of the section and a hydraulic circuit diagram. 3... Earth removal plate, 9... Working arm, 10...
Fluid pressure cylinder, 15...cover body.

Claims (1)

[Claims for Utility Model Registration] A working arm 9 is provided so that it can be vertically swung by a fluid pressure cylinder 10 provided on its lower side, and an earth removal plate 3 can be driven and raised and lowered below the working arm 9. A device for detecting upward displacement of the cover body 10, in which a cover body 15 covering the lower part of the cylinder 10 is attached to the cylinder 10 so as to be movable up and down and biased downward. A work vehicle characterized in that the detection device is connected to a safety mechanism so as to automatically operate the safety mechanism upon detection. The work vehicle according to claim 1, wherein the safety mechanism is an alarm device. The working vehicle according to claim 1, wherein the safety mechanism is a mechanism for stopping the operation of the cylinder 10.